Different clinical courses and predictors of atrial fibrillation occurrence after transisthmic ablation in patients with preablation lone atrial flutter, coexistent atrial fibrillation, and drug induced atrial flutter

The aim of this prospective study was to compare the long-term follow-up after transisthmic ablation of patients with preablation lone atrial flutter, coexistent AF, and drug induced atria] flutter to determine if postablation AF followed a different clinical course and displayed different predictors in these groups. The study evaluated 357 patients who underwent transisthmic ablation for typical atria] flutter. These were divided into four groups according to their preablotion history. Group A included patients with typical atria] flutter and without preablation AF (n = 120, 33.6%). Group B included patients with preablation AF and spontaneous atrial flutter (n = 132, 37.0 %). Group C patients had preablation AF and atrial flutter induced by treatment with IC drugs (propafenone or flecoinide) (n = 63, 17.6%) Group D included patients with preablation AF and atria] flutter induced by treatment with amiodarone (n = 42,11.8%). During a mean follow-up of 15.2 double dagger 10.6 months (range 6-55 months) AF occurred more frequently in groupsB (56.1 %) and C(57.1 %)patients than in groupsA (20.8%, P < 0.0001) ondD (31.0%, P < 0.0001) patients. The results of multivariate analysis revealed that different clinical and echocardiographical variables were correlated with postablation AF occurrence in the different groups. Patients with atria] flutter induced by amiodarone have a significantly lower risk of postablation AF than patients with spontaneous atrial flutter and AF, and those with atrialflutter induced by IC drugs. Different clinical and echocurdiographicul variables predict postablation AF occurrence in different subgroups of patients.